had had numerous possibilities of exercising its right of defense, which it did by presenting a series of documents answering the petitioners’ allegations, together with official documents relating to the judicial proceedings against the alleged victim. The Commission added that Admissibility and Merits Report No. 380/20 indicated that it had accepted the State’s position in relation to some aspects of the petition and declared that certain rights alleged by the petitioner had not been violated. It therefore considered that the State had been able to exercise its procedural rights during the procedure before the Commission, and that it had not been able to prove that a ”grave error” had been committed that would render the case inadmissible. Consequently, the Commission held that the State’s request for the control of legality was unwarranted. 20. The representatives argued that the purpose of the petition was always clear because the factual framework of the case had always been the criminal proceedings and the numerous procedural violations that had occurred. Also, the Commission had processed “everything indicated in the petitioner’s briefs and their annexes, and the information held by the State, without exception.” Furthermore, they asserted that the State had not specified why the consolidation of the admissibility and merits stages violated its rights. They added that the procedural complexity alleged by the State did not exist because there had always been certainty in relation to the elements and purpose of the petition. A.2. Considerations of the Court 21. This Court has repeatedly indicated that, pursuant to the American Convention, the Inter-American Commission has autonomy and independence in the exercise of its mandate and, in particular, in relation to the processing of individual petitions.6 The Court has the authority to conduct a control of legality when the parties make a substantiated request for this, justifying that a grave error had been committed that violated the right of defense and distorted procedural equality.7 22. The Court has required that the party arguing that the Commission’s actions have violated its rights must prove this prejudice and that it is not sufficient merely to argue a disagreement with the criteria or actions of the Commission for the Court to declare that this preliminary objection is admissible.8 23. In such cases, the Court must review the Commission’s actions when substantiating the petition to ensure that the requirements of admissibility, and also Cf. Control of Due Process in the Exercise of the Powers of the Inter-American Commission on Human Rights (Articles 41 and 44 to 51 of the American Convention on Human Rights). Advisory Opinion OC-19/05 of November 28, 2005. Series A No.19, first and third operative paragraphs; Case of the Saramaka People v. Suriname. Preliminary objections, merits, reparations and costs. Judgment of November 28,2007. Series C No. 172, para. 32, and Case of Olivera Fuentes v. Peru. Preliminary objections, merits, reparations and costs. Judgment of February 4, 2023. Series C No. 484, para. 18. 6 7 Cf. Case of the Dismissed Congressional Employees (Aguado Alfaro et al.) v. Peru. Preliminary objections, merits, reparations and costs. Judgment of November 24, 2006. Series C No. 158, para. 66, and Case of Baraona Bray v. Chile. Preliminary objections, merits, reparations and costs. Judgment of November 24, 2022. Series C No. 481, para. 23. 8 Cf. Case of the Saramaka People v. Suriname, supra, para. 32, and Case of Baraona Bray v. Chile, supra, para. 23. 6